Sodium chloride as effective antifungal treatment for artificial egg incubation inAustropotamobius pallipes

Abstract

In this study, sodium chloride at three different concentrations, 30 000 ppm (S30), 60 000 ppm (S60) and 90 000 ppm (S90), and formaldehyde at one concentration, 3000 ppm (F), were tested as antifungal chemicals during artificial incubation (AI) of Austropotamobius pallipes eggs. Two treatments were tested without chemicals as control groups with (R) and without (C) the removal of dead eggs. After AI, formaldehyde treatment ensured high survival of stage 1 (89.7 ± 2.3%) and stage 2 (85.5 ± 2.4%) of juveniles. However, comparable survival rate to stage 1 and stage 2 (85.5 ± 5.5% and 80.6 ± 3.2%) were also found in the treatment with the highest sodium chloride concentration (S90). Significantly lower survival rate of juveniles (stage 1: 60.6–70.3% and stage 2: 56.1–67.3%) were evident in groups S60, S30 and R. However, group R demanded high labor and related costs. The lowest juvenile survival levels to stage 1 (46.4 ± 8.2%) and stage 2 (45.2 ± 6.8%) were observed in treatments without fungicide chemicals and removal of dead eggs (C).